No one can anymore doubt about the increase of wireless communications between individuals. Meanwhile, if a lot of work has been done in the field of cellular communications, lots remains to be done in wireless communications involving data. In fact, it is important for a mobile user to be able to wireless communicate using his computer and a cellular phone for instance. Several solutions exists already. Meanwhile, they suffer from various limitations.
For instance, there exists wireless LAN cards (NOKIA C110 Wireless LAN card for instance) which uses PCMCIA interface to access a wireless LAN. This type of card suffers from a few limitations. The user must use the frequency of the LAN card to communicate with a hub and therefore the user cannot use his own radio system to transfer data. In the case of the NOKIA system, the typical range indoors is 30/90 m.
Furthermore, the system uses a Dynamic Host Configuration Protocol (DHCP) meaning that the IP address of the mobile is not static. This can be a serious drawback when the user wants to access a service where part of the authentification is done using a fixed IP address rather than a range of IP addresses. The encryption of the data is done using an up to 128-bit key (using Wired Equivalent Privacy protocol). It would be interesting to use any type of encryption scheme.
Another prior art technique is the use of a cellular modem in the case of an analog cellular protocol, such as AMPS. The cellular modem is usually a PCMCIA type card that the user will insert in the mobile computer. This cellular modem is then connected to a cellular telephone allowing the mobile computer to be connected to the analog cellular network. In the case of a digital cellular network, a modem is not necessary as the computer and the phone both work in digital mode. Only Terminal Adapter Equipment (TAE) is required to link the cellular phone to the computer. An Infra Red (IR) interface can be used to do so in the case that the mobile computer and the mobile are both IR compliant. In both cases, the user can then access, using the dial-up link, a data network. For instance, the user can connect to an ISP to obtain either a static or a dynamic IP address depending on the user's account. The user can also connect to his office using NetBEUI protocol. While the radio protocol has specific compression/encryption schemes, no compression/encryption procedure is done prior to the transmission of the data over the cellular phone. This is a serious issue, especially if the cellular transmission is intercepted.
Therefore there is a need for an architecture that will avoid the shortcomings of the relevant prior art.